The main sites of ROS production in mammalian cells are mitochondria [69], , in turn,and its generation is initiated by the electron leak primarily at complex I through partial reduction of molecular oxygen (O₂) to superoxide radical (O₂*-) by a single electron uptakeit leads to either hydroxyl radical (OH*) generation through iron catalyzed Fenton reaction or to peroxynitrite (ONOO−) (Fig. 3).Superoxide radical (O₂*-) also converted to hydrogen peroxide (H2O2) superoxide dismutase 2Dopamine in PD brain is oxidized to form dopamine quinones and free radicals either by self-oxidation or by mitochondrial outer membrane bound monoamine oxidase (MAO) such as MAO-A (in neurons) and MAO-B (in glia). [Oxidation products of dopamine may cycle to form aminochrome, and are reactive enough to produce superoxide radicals (?)]

Above mainly 2019 Raza

Evidence in PD

csfBlood
(Khan, 2018 #582)
(Wei, 2018 #581)Looks better than Khan 2018Nothing is significant

Measurement of OS

Redox stateOxidized DNAOxysterol
exampleexampleExample
GSH/GSSG ratio, ↓ is stressAmathus, Rat SN8-OHdG, ↑ is stressAmathus, Rat SN7β-HC, ↑ is stressAmathus, Rat SN

Route of Administration

ICM (= Suboccipital puncture)

  • Biodistribution
    • WORLDSympsium 2021 Pukenas: 대략, cortxt에 잘 분포함 (deep structure eg. striatum, thalamus, midbrain 시키)
  • Toxicity
    • DRG axonopathy,
    • Dorsal spinal column axonopathy
    • Inflammatory cell infiltrates

(Sagittal mouse-brain anatomical illustration with labels: Arachnoid mater, Lateral ventricle, Third ventricle, Fourth ventricle, Subarachnoid space, Cisterna magna; CP markers in red. Source: Molecular Pharmaceutics 2018; 15 (3): 911-922.)

  • → staggered dosing in every cohort, is recommended (assessment of upper and lower limb somatosensory evoked potential (SSEP)
  • Examples
MPSIINCT03566043RGX-121ICM
MPS1NCT03580083RGX-111ICV
MPS1IISRGX-111ICM

Route of administration: Intra-cisterna magna (ICM) injection

Quotes from KOL callouts on the slide:

  • Ronald Crystal, MD, Weill Cornell Medicine on his ICM approach: “so we decided to do C1 or C2 injection. It’s done under CT scanning, it’s an outpatient procedure, and it takes about 25 to 30 minutes to place the needle, and about 5 minutes to administer. So far, we’ve treated 3 patients” (Nov 23, 2020)
  • Prof. Jason Sheehan, Vice Chair – Dep. Neurosurgery, Univ. Virginia and performing ICM injection. The procedure is done under sedation and depending on volume can be completed in 45 min with CT scanning. MRI scanning would also work. (Nov 2020)
  • Robert P. Allen, MD, Interventional Radiologist, Denver, CO is planning ICM injections, experienced in IT and plans to use CT for imaging. Total procedure should be about 30 minutes. He believes that it will become an outpatient procedure.

Confidential - for internal use only

IndicationSponsorStageAAV SerotypeTx PayloadNo. of patients dosedComments
Tay-Sachs, Sandhoff'sAxovant /Sio Gene TxPhase 1/2 NCT04669535AAVrh8HEXA/ HEXB AXO-AAV-GM2(2)Treated under investigator initiated trial
No AE reported1
GBA-PDPrevail Tx / LillyPhase 1/2 NCT04127578AAV9GBA1 PR001A1No procedure-related complications, well-tolerated
Gaucher Type 2Prevail Tx / LillyPhase 1/2 NCT04411654AAV9GBA1 PR001(2)Treated under compassionate use
No procedure-related complications, well-tolerated
MPSIRegenxBioPhase 1/2 NCT03580083AAV9IDUA RGX-1111Well-tolerated and no severe AEs3
MPSIIRegenxBioPhase 1/2 NCT03566043AAV9IDS RGX-1213Well-tolerated and no severe AEs3
FTDPrevail Tx / LillyPhase 1/2 NCT04408625AAV9GRN PR0061Dec 2020
GM1 gangliosidosisPassageBioPhase 1/2 NCT04713475AAVhu68GLB1 PBGM01Recruiting
Alzheimer's diseaseLexeoTxPhase 1/2 NCT03634007AAVrh10APOE2 LX10013C1/C2 injection with CT
FTDPassageBioPhase 1/2 NCT04747431AAV1GRN PBFT02Not yet recruiting
KrabbePassageBioPhase 1/2 NCT04771416AAVhu68GALC PBKR03Not yet recruiting

ICM RISKS: ICM procedure risks are all the standard risks associated with a procedure: Bleeding, infection, CSF leak, spinal headache (~5-10%), meningitis, damage to brainstem/cerebellum

1. T. Flotte presentation …
2. Zsuli et al. Poster at …
3. RegenxBio media release …

Peripheral leak/transduction in ICM

{Hauricot, 2013 #1613}dog Vector biodistribution following i.c. delivery of AAV9-GFP vectors to dogs
SlowFast
Dog 1Dog 2Dog 3Dog 4
CNS
Rhinencephalon1.82-3.41.62-5.8615.361.72-4.2
Dorsal frontal cortex5.85-6.582.36-3.342.20-3.055.4-6.2
Medial frontal cortex3.821.671.491.24
Dorsal parietal cortex1.070.031.681.93
Lateral parietal cortex3.076.930.66.2
Temporal cortex2.142.60.433.26
Piriform lobe16.433.983.9811
Hippocampus0.821.493.750.86
Pons3.250.310.13.37
Cerebellum0.27-0.40.32-0.782-3.60.18-0.38
Medulla oblongata0.3-1.171.22NA2.42-7.12
C3-C6NA0.34-0.5110.397.22
Somatic tissues
Liver4.72-6.611.75-1.524.13-7.772.73-1.54
Heart0.090.050.240.01
Lung0.220.120.480.04
Spleen4.121.6817.733.24
Pancreas000.010
Intestine0.070.010.030.02
Kidney0.220.490.250.26
Skeletal muscle0.230.130.250.04
Gonads0.030.010.120.02
Cervical LN2.91.823.690.01
Popliteal LNNANA0.420.56
Vector genome copy numbers were determined in different brain areas and in several somatic organs in dogs receiving slow or fast infusions of 2 × 10¹³ vg of AAV9-GFP vectors to the cisterna magna (Dogs 1-4). For those specimens for which 2 samples were available, both values are provided. NA, not available.
{nderer, 2018 #14}dog(Bar chart GC / Diploid Genome on log scale showing organ-specific transduction across multiple tissues, three coloured bars per tissue. Continues on next photo.)

Uncertain Spans

locationtranscriptionuncertainty
WORLDSympsium 2021 bullet대략, cortxt에 잘 분포함 (deep structure eg. striatum, thalamus, midbrain 시키)The trailing Korean shorthand 시키 reads as written; OCR returns the same string in both engines.
Hauricot 2013 #1613 row labelcitation tagOCR returns Hauricot, 2013 #1613 but the surname may be Haurigot (Spanish researcher); preserved as printed in this capture.
Bottom row author tag{nderer, 2018 #14}The leading author surname is partly cropped by the table’s left edge; only nderer is visible (likely Hinderer 2018).